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May 22 tornado coincidences

Is it just me, or does there seem to have been a huge number of violent tornadoes on May 22?

May 22, 1893- F5 tornado in Willow Springs, Wisconsin.
May 22, 1933- F5 tornado in Tryon, Nebraska.
May 22, 1952- F4 tornado in Douglas County, Kansas.
May 22, 1981- F4 tornado in Binger, Oklahoma.
May 22, 2004- F4 tornado in Hallam, Nebraska.
May 22, 2011- EF5 tornado in Joplin, Missouri.

And I'm sure I'm missing a few...So why is it this day that almost looks like it has a "tornado curse" on it? Obviously it's near the peak of the season, but why have there been so many years with violent tornadoes on May 22 specifically? I'm pretty sure it's just coincidence, but I thought I'd share.
Yeah I think if you look hard enough you can probably find many days that you could say that about. Here's one I did for April 3rd:

1956- 4 F4's, 1 F5 (Hudsonville, MI)
1964- 1 F5 in Wichita Falls, TX
1968- 2 F4's in AR and MI
1974- Super Outbreak- 23 F4's and 7 F5's
1981- 1 F4 in Madison County, IL
1999- 1 F4 in Benton, LA
Oooh I really like topics like this. From the SPC tornado database, I plotted/sorted the number of EF4 or 5 tornadoes. There have been 617 violent tornadoes since 1950, and this is how they are distributed by dates. Obviously, the big outbreak days like Apr 3, 1974 and Apr 27, 2011 can really skew the tornado count on a particular date.

This thread seemed more interested in dates that had lots of violent tornadoes spread across many different years. Removing "duplicate" tornadoes from the same day and year, this is the distribution.
Interestingly, May-5 has had a violent tornado on 8 separate years (60, 61, 64, 65, 77, 89, 93, and 99), so I'd rank that one as the "most coincidental" in the spirit of this thread. Note that Apr-3 and Apr-27 still rank really well (i.e. their high count in the first graph was not solely from one outbreak event). I was kinda surprised to see Jun-8 with 6 separate violent tornado years, which is later than the other high-count days.